Inflammatory cytokines and mucosal injury

Inhibiting the CB1 receptor in CIH-induced animal model alleviates colon injury

Obstructive sleep apnea (OSA) can lead to intestinal injury, endotoxemia, and disturbance of intestinal flora. Additionally, as a crucial component of the endocannabinoid system, some studies have demonstrated that cannabinoid 1 (CB1) receptors are closely linked to the multiple organ dysfunction triggered by OSA. However, the role of the CB1 receptor in alleviating OSA-induced colon injury remains unclear. Here, through the construction of the OSA classic model, we found that the colon tissue of chronic intermittent hypoxia (CIH)-induced mice exhibited an overexpression of the CB1 receptor. The results of hematoxylin-eosin staining and transmission electron microscopy revealed that inhibition of the CB1 receptor could decrease the gap between the mucosa and muscularis mucosae, alleviate mitochondrial swelling, reduce microvilli shedding, and promote the recovery of tight junctions of CIH-induced mice. Furthermore, CB1 receptor inhibition reduced the levels of metabolic endotoxemia and inflammatory responses, exhibiting significant protective effects on the colon injury caused by CIH. At the molecular level, through western blotting and real-time polymerase chain reaction techniques, we found that inhibiting the CB1 receptor can significantly increase the expression of ZO-1 and Occludin proteins, which are closely related to the maintenance of intestinal mucosal barrier function. Through 16S rRNA high-throughput sequencing and short-chain fatty acid (SCFA) determination, we found that inhibition of the CB1 receptor increased the diversity of the microbial flora and controlled the makeup of intestinal flora. Moreover, butyric acid concentration and the amount of SCFA-producing bacteria, such as Ruminococcaceae and Lachnospiraceae, were both markedly elevated by CB1 receptor inhibition. The results of the spearman correlation study indicated that Lachnospiraceae showed a positive association with both ZO-1 and Occludin but was negatively correlated with the colon CB1 receptor, IL-1β, and TNF-α. According to this study, we found that inhibiting CB1 receptor can improve CIH-induced colon injury by regulating gut microbiota, reducing mucosal damage and promoting tight junction recovery. KEY POINTS: •CIH leads to overexpression of CB1 receptor in colon tissue. •CIH causes intestinal flora disorder, intestinal mucosal damage, and disruption of tight junctions. •Inhibition of CB1 receptor can alleviate the colon injury caused by CIH through regulating the gut microbiota, reducing mucosal injury, and promoting tight junction recovery.

Intestinal barrier functions in hematologic and oncologic diseases

The intestinal barrier is a complex structure that not only regulates the influx of luminal contents into the systemic circulation but is also involved in immune, microbial, and metabolic homeostasis. Evidence implicating disruption in intestinal barrier functions in the development of many systemic diseases, ranging from non-alcoholic steatohepatitis to autism, or systemic complications of intestinal disorders has increased rapidly in recent years, raising the possibility of the intestinal barrier as a potential target for therapeutic intervention to alter the course and mitigate the complications associated with these diseases. In addition to the disease process being associated with a breach in the intestinal barrier functions, patients with hematologic and oncologic diseases are particularly at high risks for the development of increased intestinal permeability, due to the frequent use of broad-spectrum antibiotics and chemoradiation. They also face a distinct challenge of being intermittently severely neutropenic due to treatment of the underlying conditions. In this review, we will discuss how hematologic and oncologic diseases are associated with disruption in the intestinal barrier and highlight the complications associated with an increase in the intestinal permeability. We will explore methods to modulate the complication. To provide a background for our discussion, we will first examine the structure and appraise the methods of evaluation of the intestinal barrier.

Oral delivery of IL-22 mRNA-loaded lipid nanoparticles targeting the injured intestinal mucosa: A novel therapeutic solution to treat ulcerative colitis

Oral mRNA delivery is a promising yet understudied approach for treating inflammatory bowel disease (IBD). Inspired by the colon-targeting ability of ginger-derived nanoparticles (GDNPs), we reversely engineered lipid nanoparticles that comprise the three major lipids identified in GDNPs. When mixed at the ratio found in GDNPs, the selected lipids (phosphatidic acid, monogalactosyldiacylglycerol, and digalactosyldiacylglycerol; 5:2:3) self-assembled into new lipid nanoparticles (nLNPs) in phosphate-buffered saline. We encapsulated IL-22-mRNA within the nLNPs, as enhanced IL-22 expression in the colon is known to have potent anti-inflammatory efficacy against ulcerative colitis (UC). The IL-22 mRNA-loaded nLNPs (IL-22/nLNPs) were found to be about 200 nm in diameter and have a zeta potential of -18 mV. Oral delivery of IL-22/nLNPs elevated the protein expression level of IL-22 in the colonic mucosa of mice. In a mouse model of acute colitis, mice fed with IL-22/nLNPs experienced an accelerated healing process, as indicated by the recovery of more body weight and colon length as well as reduction of the histological index, colonic MPO activity, fecal lipocalin concentration, and mRNA expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1β). Our results suggest that our reversely engineered nLNPs is an excellent mRNA delivery platform for treating ulcerative colitis.

Protective effects of glycine against lipopolysaccharide-induced intestinal apoptosis and inflammation

Intestinal dysfunction is commonly observed in humans and animals. Glycine (Gly) is a functional amino acid with anti-inflammatory and anti-apoptotic properties. The objective of this study was to test the protective effects of Gly against lipopolysaccharide (LPS)-induced intestinal injury. 28 C57BL/6 mice with a body weight (BW) of 18 ± 2 g were randomly assigned into four groups: CON (control), GLY (orally administered Gly, 5 g/kg BW/day for 6 days), LPS (5 mg/kg BW on day 7, i. p.), and GLY + LPS (Gly pretreatment and LPS administration). Histological alterations, inflammatory responses, epithelial cell apoptosis, and changes of the intestinal microbiota were analyzed. Results showed that, compared with the CON group, mice in the LPS treatment group showed decreased villus height, increased crypt depth, and decreased ratio of villus height to crypt depth, which were significantly attenuated by Gly. Neither LPS nor Gly treatment altered morphology of the distal colon tissues. LPS increased the apoptosis of jejunum and colon epithelial cells and protein abundance of cleaved caspase3 in the jejunum, which were markedly abrogated by Gly. LPS also elevated the mRNA levels of Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MYD88), pro-inflammatory cytokines, and chemokines in the jejunum and colon. These alterations were significantly suppressed by Gly. In addition, Gly supplementation attenuated infiltration of CD4+, CD8+ T-lymphocytes, CD11b+ and F4/80+ macrophages in the colon. Furthermore, Gly increased the relative abundance of Mucispirillum, Lachnospiraceae-NK4A136-group, Anaerotruncus, Faecalibaculum, Ruminococcaceae-UCG-014, and decreased the abundance of Bacteroides at genus level. Supplementation with Gly might be a nutritional strategy to ameliorate LPS-induced intestinal injury in mice.

Intestinal pathophysiological abnormalities in steady state and after vaso-occlusive crisis in murine sickle cell disease

We showed in the present study that, not unlike in adult patients with sickle cell disease (SCD), Townes mice exhibit increases in serum intestinal fatty acid binding proteins and lipopolysaccharides (LPS), together with a breach in the intestinal barrier. These abnormalities increased rapidly after the induction of vaso-occlusive crisis (VOC). We also confirmed higher intestinal microbial density in SCD. These findings support the concept that SCD and/or its complications, and not hospitalisation or medications, are responsible for the intestinal pathophysiological changes. The present results provide the basis for use of Townes mice to further elucidate the mechanistic relationship between intestinal pathophysiology and VOC.

A Pegylated Flavin Adenine Dinucleotide PEG Complex to Boost Immunogenic and Therapeutic Effects in a Liver Cancer Model

Flavin adenine dinucleotide (FAD) is engaged in several metabolic diseases. Its main role is being a cofactor essential for the activity of many flavoproteins, which play a crucial role in electron transport pathways in living systems. The aim of this study was to apply a pegylated flavins formulation named FAD-PEG diacide complex as theranostic pathway in cancer therapy. For this purpose, a mouse liver cancer model induced by Hepa1-6 cells was used to evaluate the therapeutic efficacy of FAD (named NP1) and FAD-PEG diacide complex (named NP2). The cytokines were applied to screen the serum inflammatory factors, to establish the blood cell content of different groups of nude mice. The highlights follows that FAD formulations (NP1; NP2) significantly suppressed the tumor growth and reduced the tumor index without effects on the body weight of mice. Furthermore, NP2 significantly reduced the serum levels of cytokines IL-6, TNF-α and IL-12 (P70). The reported results provide the proof-of-concept for the synthesis of a smart adjuvant for liver cancer therapy and support their further development in the field of nanomedicine.

Immune Modulation Effects of Lactobacillus casei Variety rhamnosus on Enterocytes and Intestinal Stem Cells in a 5-FU-Induced Mucositis Mouse Model

Background

Intestinal mucositis remains one of the most deleterious side effects in cancer patients undergoing chemotherapy. We hypothesize that the probiotics could preserve gut ecology, ameliorate inflammation, and protect epithelia via immune modulations of enterocytes and intestinal stem cells. Our aim is to characterize these changes and the safety of probiotics via a 5-fluorouracil- (5-FU-) induced intestinal mucositis mouse model.

Methods

5-FU-injected BALB/c mice were either orally administrated with saline or probiotic suspension of Lactobacillus casei variety rhamnosus (Lcr35). Diarrhea scores, serum proinflammatory cytokines, and T-cell subtypes were assessed. Immunostaining analyses for the proliferation of intestinal stem cells CD44 and Ki67 were processed. Samples of blood and internal organs were investigated for bacterial translocation.

Results

Diarrhea was attenuated after oral Lcr35 administration. Serum proinflammatory cytokines were significantly increased in the 5-FU group and were reversed by Lcr35. A tremendous rise of the CD3⁺/CD8⁺ count and a significant decrease of CD3⁺CD4⁺/CD3⁺CD8⁺ ratios were found in the 5-FU group and were both reversed by Lcr35. 5-FU significantly stimulated the expression of CD44 stem cells, and the expression was restored by Lcr35. 5-FU could increase the number of Ki67 proliferative cells. No bacterial translocation was found in this study.

Conclusions

Our results showed that 5-FU caused intestinal inflammation mainly via Th1 and Th17 responses. 5-FU could stimulate stem cells and proliferation cells in a mouse model. We demonstrate chemotherapy could decrease immune competence. Probiotics were shown to modulate the immune response. This is the first study to analyze the immune modulation effects and safety of Lactobacillus strain on enterocytes and intestinal stem cells in a mouse model.

The association between HPV gene expression, inflammatory agents and cellular genes involved in EMT in lung cancer tissue

BACKGROUND

Lung cancer is a leading cause of cancer morbidity and mortality worldwide. Several studies have suggested that Human papillomavirus (HPV) infection is an important risk factor in the development of lung cancer. In this study, we aim to address the role of HPV in the development of lung cancer mechanistically by examining the induction of inflammation and epithelial-mesenchymal transition (EMT) by this virus.

METHODS

In this case-control study, tissue samples were collected from 102 cases with lung cancer and 48 controls. We examined the presence of HPV DNA and also the viral genotype in positive samples. We also examined the expression of viral genes (E2, E6 and E7), anti-carcinogenic genes (p53, retinoblastoma (RB)), and inflammatory cytokines in HPV positive cases.

RESULTS

HPV DNA was detected in 52.9% (54/102) of the case samples and in 25% (12/48) of controls. A significant association was observed between a HPV positive status and lung cancer (OR = 3.37, 95% C.I = 1.58-7.22, P = 0.001). The most prevalent virus genotype in the patients was type 16 (38.8%). The expression of p53 and RB were decreased while and inflammatory cytokines were increased in HPV-positive lung cancer and HPV-positive control tissues compared to HPV-negative lung cancer and HPV-negative control tissues. Also, the expression level of E-cad and PTPN-13 genes were decreased in HPV- positive samples while the expression level of SLUG, TWIST and N-cad was increased in HPV-positive samples compared to negative samples.

CONCLUSION

Our study suggests that HPV infection drives the induction of inflammation and EMT which may promote in the development of lung cancer.

Radioprotective Effects of Dermatan Sulfate in a Preclinical Model of Oral Mucositis-Targeting Inflammation, Hypoxia and Junction Proteins without Stimulating Proliferation

Oral mucositis is the most frequently occurring early side effect of head-and-neck cancer radiotherapy. Systemic dermatan sulfate (DS) treatment revealed a significant radioprotective potential in a preclinical model of oral mucositis. This study was initiated to elucidate the mechanistic effects of DS in the same model. Irradiation comprised daily fractionated irradiation (5 × 3 Gy/week) over two weeks, either alone (IR) or in combination with daily dermatan sulfate treatment of 4 mg/kg (IR + DS). Groups of mice (n = 5) were sacrificed every second day over the course of 14 days in both experimental arms, their tongues excised and evaluated. The response to irradiation with and without DS was analyzed on a morphological (cell numbers, epithelial thickness) as well as on a functional (proliferation and expression of inflammation, hypoxia and epithelial junction markers) level. The mucoprotective activity of DS can be attributed to a combination of various effects, comprising increased expression of epithelial junctions, reduced inflammation and reduced hypoxia. No DS-mediated effect on proliferation was observed. DS demonstrated a significant mucositis-ameliorating activity and could provide a promising strategy for mucositis treatment, based on targeting specific, radiation-induced, mucositis-associated signaling without stimulating proliferation.

Early inflammatory changes in radiation-induced oral mucositis : Effect of pentoxifylline in a mouse model

Purpose

Early inflammation is a major factor of mucosal reactions to radiotherapy. Pentoxifylline administration resulted in a significant amelioration of radiation-induced oral mucositis in the mouse tongue model. The underlying mechanisms may be related to the immunomodulatory properties of the drug. The present study hence focuses on the manifestation of early inflammatory changes in mouse tongue during daily fractionated irradiation and their potential modulation by pentoxifylline.

Materials and methods

Daily fractionated irradiation with 5 fractions of 3 Gy/week (days 0–4, 7–11) was given to the snouts of mice. Groups of 3 animals per day were euthanized every second day between day 0 and 14. Pentoxifylline (15 mg/kg, s. c.) was administered daily from day 5 to the day before sacrifice. The expression of the inflammatory proteins TNFα, NF-κB, and IL-1β were analysed.

Results

Fractionated irradiation increased the expression of all inflammatory markers. Pentoxifylline significantly reduced the expression of TNFα and IL-1β, but not NF-κB.

Conclusion

Early inflammation, as indicated by the expression of the inflammatory markers TNFα, NF-κB, and IL-1β, is an essential component of early radiogenic oral mucositis. Pentoxifylline differentially modulated the expression of different inflammatory markers. The mucoprotective effect of pentoxifylline does not appear to be based on modulation of NF-κB-associated inflammation.

Carvacrol reduces irinotecan-induced intestinal mucositis through inhibition of inflammation and oxidative damage via TRPA1 receptor activation

Intestinal mucositis is an inflammatory process occurring in the intestinal mucosa and is a common side effect of irinotecan hydrochloride (CPT-11) based anticancer regimens. The transient receptor potential cation channel, subfamily A, member 1 (TRPA1) receptor is highly expressed in the intestinal mucosa and has the ability to identify cell damage signaling indicates its possible association with intestinal mucositis. Carvacrol is an agonist of the TRPA1 receptor and has anti-inflammatory properties. Thus, the aim of the present study was to verify the supposed anti-inflammatory and protective action of carvacrol via TRPA1 activation against intestinal mucositis induced by CPT-11 in mice. Briefly, mice were treated with either DMSO 2% or CPT-11 (75 mg/kg, per 4 days, i.p.) or the carvacrol (25, 75 or 150 mg/kg, per 8 days, i.p.) before CPT-11. In other group, the animals were pretreated with HC-030031, a TRPA1 antagonist, 30 min before treatment with carvacrol. On day 7, animal survival and bacteremia were assessed, and following euthanasia, samples of the jejunum were obtained for morphometric analysis and measurement of antioxidant and pro-inflammatory markers. Carvacrol was found to exert an anti-inflammatory action against CPT-11-induced intestinal mucositis through strong interactions with TRPA1 receptors; reduction in the production or release or both of pro-inflammatory cytokines (TNF-α, IL-1β, and KC); and decrease in other indicators of inflammation (MPO, NF-κB, COX-2) and oxidative stress (GSH, MDA, and NOx levels). It also contributed to the restoration of the tissue architecture of the villi and crypts in the small intestine, and improved clinical parameters such as survival, body mass variation, leukogram, and blood bacterial count. Thus, TRPA1 could be a target for future therapeutic approaches in the treatment of intestinal mucositis.

Protective effect and potential mechanisms of Wei-Chang-An pill on high-dose 5-fluorouracil-induced intestinal mucositis in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Wei-Chang-An pill (WCA pill), a traditional Chinese pharmaceutical preparation, possessed potential anti-inflammatory advantages and noteworthy gastrointestinal regulations in digestive diseases, which might represent a promising candidate for the treatment of intestinal mucositis (IM) induced by 5-fluorouracil (5-FU).

AIM OF THE STUDY

To analyze the bioactive constituents and investigate the effect of methanol extraction from WCA pill (WCA ext) on 5-FU induced IM with underlying mechanisms.

MATERIALS AND METHODS

The analysis of serum bioactive constituents after WCA ext administration in rats was carried out by UHPLC-Quadrupole-Time of Flight-Mass Spectrometry. In mice, IM was induced by 5-FU and physical manifestations were measured during the period of drug delivery. Half of mice were assessed with histology, expression of inflammatory cytokines in ileum and plasma via hematoxylin and eosin staining, immunohistochemical staining as well as cytokine enzyme-linked immunosorbent assay test, respectively. Besides, gastric emptying (GE) and gastrointestinal transit (GIT) were further tested in the other half of 5-FU induced mice.

RESULTS

Twenty-two compounds were identified or tentatively characterized. IM induced by 5-FU was improved significantly after treatment with WCA ext through reducing the body weight loss, relieving the severe diarrhea, and inhibiting the GE as well as GIT. Further assessments validated that WCA ext promoted the recovery of intestinal mucosa, evaluated the activity of enterocyte proliferation, maintained the integrity of tight junction, and ameliorated the inflammatory disturbances.

CONCLUSIONS

These results suggested that WCA ext promoted the restoration of intestinal function in 5-FU-induced IM via regulating multiple sites of actions in intestinal homeostasis. Accordingly, WCA pill might be a promising therapeutic candidate for the prevention of IM during cancer chemotherapy.

Administration of probiotic mixture DM#1 ameliorated 5-fluorouracil-induced intestinal mucositis and dysbiosis in rats

OBJECTIVE

The use of probiotics to alleviate chemotherapy-induced intestinal mucositis is supported by clinical consensus. However, no studies to date, to our knowledge, have systematically analyzed the effects of a probiotic mixture on chemotherapy-induced mucositis or assessed changes in the intestinal microbiota after probiotic treatment. The aim of this study was to report the effects of a probiotic mixture, DM#1, on intestinal mucositis and dysbiosis of rats treated with 5-fluorouracil (5-FU).

METHODS

Twenty-eight male Sprague Dawley rats weighing 180 to 220 g were randomly divided into four groups: control, 5-FU, probiotic high (PH), and probiotic low (PL). Except for the control group, all other groups received intraperitoneal injections of 5-FU for 5 d, and the PH and PL groups received DM#1 intragastrically (1 × 10⁹ or 1 × 10⁸ colony-forming units/kg, respectively) for 8 d. One day after the last administration, rats were sacrificed and the ilea were removed for histopathologic assessment and evaluation of permeability, myeloperoxidase activity, levels of cytokines (interleukin [IL]-4, IL-6, tumor necrosis factor [TNF]-α), and mRNA of toll-like receptors (TLR; TLR2, TLR4, and TLR9). Additionally, intestinal microbiota profiles were analyzed by polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis and quantitative real-time PCR.

RESULTS

Treatment with DM#1 ameliorated 5-FU-induced intestinal mucosal injury in rats, possibly by reducing proinflammatory cytokine levels and neutrophil infiltration. The increased intestinal permeability caused by 5-FU was ameliorated. These results were closely associated with the reestablishment of intestinal microbial homeostasis and alteration of the TLR2/TLR4 signaling pathway.

CONCLUSIONS

Administration of the probiotic mixture DM#1 ameliorated 5-FU-induced intestinal mucositis and dysbiosis in rats.

Chronic Inflammation-Related HPV: A Driving Force Speeds Oropharyngeal Carcinogenesis

Oropharyngeal squamous cell carcinoma (OPSCC) has been known to be a highly aggressive disease associated with human papilloma virus (HPV) infection. To investigate the relationship between HPV and chronic inflammation in oropharyngeal carcinogenesis, we collected 140 oral mucous fresh specimens including 50 OPSCC patients, 50 cancer in situ, 30 precancerous lesions, and 10 normal oral mucous. Our data demonstrated that there was a significantly higher proportion of severe chronic inflammation in dysplastic epithelia in comparison with that in normal tissues (P<0.001). The positive rate of HPV 16 was parallel with the chronic inflammation degrees from mild to severe inflammation (P<0.05). The positive rate of HPV 16 was progressively improved with the malignant progression of oral mucous (P<0.05). In addition, CD11b+ LIN- HLA-DR-CD33+ MDSCs were a critical cell population that mediates inflammation response and immune suppression in HPV-positive OPSCC. These indicated that persistent chronic inflammation-related HPV infection might drive oropharyngeal carcinogenesis and MDSCs might pay an important role during this process. Thus, a combination of HPV infection and inflammation expression might become a helpful biomedical marker to predict oropharyngeal carcinogenesis.

Inflammatory intestinal damage induced by 5-fluorouracil requires IL-4

BACKGROUND

5-Fluorouracil (5-FU) induces intestinal mucositis, which is characterized by epithelial ulcerations in the mucosa and clinical manifestations, such as pain and dyspeptic symptoms. Cytokines participate in the inflammatory and functional events of intestinal mucositis. IL-4 is an important mediator of intestinal inflammation, with either anti-inflammatory or pro-inflammatory functions, depending on the model of intestinal inflammation. This study aimed to evaluate the role of IL-4 in 5-FU-induced intestinal mucositis.

METHODS

IL-4+/+ or IL-4-/- mice (25-30 g) were intraperitoneally injected with 5-FU (450 mg/Kg) or saline (C). After 3 days, the mice were sacrificed and the duodenum was evaluated for epithelial damage, MPO activity and cytokine concentration.

RESULTS

5-FU induced significant damage in the intestinal epithelium of IL-4+/+ mice (reduction in the villus/crypt ratio: control=3.31±0.21 μm, 5-FU=0.99±0.10 μm). However, the same treatment did not induce significant damage in IL-4-/- mice (5-FU=2.87±0.19 μm) compared to wild-type mice. 5-FU-induced epithelial damage increased the MPO activity (neutrophil number) and the level of pro-inflammatory cytokines (IL-4, TNF-α, IL-1β and CXCL-8) in the duodenum. These results were not observed in IL-4-/- mice treated with 5-FU.

CONCLUSION

Our data suggest that IL-4 participates as a pro-inflammatory cytokine in a 5-FU-induced intestinal damage model and suggests that IL-4 antagonists may be novel therapeutics for this condition.

Local inflammation and human papillomavirus status of head and neck cancers

OBJECTIVE

To determine whether periodontitis is associated with human papillomavirus (HPV) status of head and neck squamous cell carcinoma (HNSCC).

DESIGN AND SETTING

Hospital-based case-control study in a comprehensive cancer center.

PATIENTS

Evaluation included all patients diagnosed with incident primary squamous cell carcinoma of the oral cavity, oropharynx, and larynx between 1999 and 2007 for whom tissue samples and dental records were available (N = 124). Patients younger than 21 years and those with a history of cancer were excluded. Periodontitis history was assessed by alveolar bone loss in millimeters from panoramic radiographs by one examiner blinded to cancer status.

MAIN OUTCOME MEASURE

The presence of HPV-16 DNA in paraffin-embedded tumor samples was identified by polymerase chain reaction.

RESULTS

The prevalence of HPV-positive HNSCC was 50 of 124 patients (40.3%). A higher proportion of oropharyngeal cancers were HPV-positive (32 of 49 [65.3%]) compared with oral cavity (9 of 31 [29.0%]) and laryngeal (9 of 44 [20.5%]) cancers. Each millimeter of alveolar bone loss was associated with 2.6 times increased odds (odds ratio [OR], 2.61; 95% CI, 1.58-4.30) of HPV-positive tumor status after adjustment for age at diagnosis, sex, and smoking status. The strength of the association was greater among patients with oropharyngeal SCC (OR, 11.70; 95% CI, 2.09-65.53) compared with those with oral cavity SCC (OR, 2.32; 95% CI, 0.65-8.27) and laryngeal SCC (OR, 3.89; 95% CI, 0.95-15.99).

CONCLUSIONS

A history of chronic inflammatory disease in the oral cavity may be associated with tumor HPV status in patients with HNSCC. This association seems to be stronger among patients with oropharyngeal cancer compared with those who have oral cavity or laryngeal SCC.

Interaction between Chronic Inflammation and Oral HPV Infection in the Etiology of Head and Neck Cancers

Incidences of oral tongue, base of the tongue, and tonsil cancers have been increasing steadily in many parts of the world in spite of declining rates of tobacco use over the last four decades. A better understanding of the etiology, interactions between risk factors, and new approaches to prevention and treatment are necessary to change this course. This paper will present evidence supporting a potential role of chronic inflammation in the etiologies of oral human papillomavirus infection and head and neck squamous cell carcinoma, and it will discuss the implications for prevention and treatment.

Response of gammadelta T Cells to plant-derived tannins

Many pharmaceutical drugs arc isolated from plants used in traditional medicines, and new plant-derived pharmaceutical drugs continue to be identified. Relevant to this review, different plant-derived agonists for gammadelta T cells are described that impart effector functions upon distinct subsets of these cells. Recently, plant tannins have been defined as one class of gammadelta T cell agonist and appear to preferentially activate the mucosal population. Mucosal gammadelta T cells function to modulate tissue immune responses and induce epithelium repair. Select tannins, isolated from apple peel, rapidly induce immune gene transcription in gammadelta T cells, leading to cytokinc production and increased responsiveness to secondary signals. Activity of these tannin preparations tracks to the procyanidin fraction, with the procyanidin trimer (C1) having the most robust activity defined to date. The response to the procyanidins is evolutionarily conserved in that responses are seen with human, bovine, and murine gammadelta T cells, although human cells show less selectivity. Procyanidin-induced responses described in this review likely account for the expansion of mucosal gammadelta T cells seen in mice and rats fed soluble extracts of tannins. Use of procyanidins to activate gammadelta T cells may represent a novel approach for the treatment of tissue damage and autoimmune diseases.

Decline in intestinal mucosal IL-10 expression and decreased intestinal barrier function in a mouse model of total parenteral nutrition

Loss of intestinal epithelial barrier function (EBF) is a major problem associated with total parenteral nutrition (TPN) administration. We have previously identified intestinal intraepithelial lymphocyte (IEL)-derived interferon-gamma (IFN-gamma) as a contributing factor to this barrier loss. The objective was to determine whether other IEL-derived cytokines may also contribute to intestinal epithelial barrier breakdown. C57BL6J male mice received TPN or enteral nutrition (control) for 7 days. IEL-derived interleukin-10 (IL-10) was then measured. A significant decline in IEL-derived IL-10 expression was seen with TPN administration, a cytokine that has been shown in vitro to maintain tight junction integrity. We hypothesized that this change in IEL-derived IL-10 expression could contribute to TPN-associated barrier loss. An additional group of mice was given exogenous recombinant IL-10. Ussing chamber experiments showed that EBF markedly declined in the TPN group. TPN resulted in a significant decrease of IEL-derived IL-10 expression. The expression of several tight junction molecules also decreased with TPN administration. Exogenous IL-10 administration in TPN mice significantly attenuated the TPN-associated decline in zonula occludens (ZO)-1, E-cadherin, and occludin expression, as well as a loss of intestinal barrier function. TPN administration led to a marked decline in IEL-derived IL-10 expression. This decline was coincident with a loss of intestinal EBF. As the decline was partially attenuated with the administration of exogenous IL-10, our findings suggest that loss of IL-10 may be a contributing mechanism to TPN-associated epithelial barrier loss.

Role of cytokines (TNF-alpha, IL-1beta and KC) in the pathogenesis of CPT-11-induced intestinal mucositis in mice: effect of pentoxifylline and thalidomide

INTRODUCTION

Irinotecan (CPT-11) is an inhibitor of DNA topoisomerase I and is clinically effective against several cancers. A major toxic effect of CPT-11 is delayed diarrhea; however, the exact mechanism by which the drug induces diarrhea has not been established.

PURPOSE

Elucidate the mechanisms of induction of delayed diarrhea and determine the effects of the cytokine production inhibitor pentoxifylline (PTX) and thalidomide (TLD) in the experimental model of intestinal mucositis, induced by CPT-11.

MATERIALS AND METHODS

Intestinal mucositis was induced in male Swiss mice by intraperitoneal administration of CPT-11 (75 mg/kg) daily for 4 days. Animals received subcutaneous PTX (1.7, 5 and 15 mg/kg) or TLD (15, 30, 60 mg/kg) or 0.5 ml of saline daily for 5 and 7 days, starting 1 day before the first CPT-11 injection. The incidence of delayed diarrhea was monitored by scores and the animals were sacrificed on the 5th and 7th experimental day for histological analysis, immunohistochemistry for TNF-alpha and assay of myeloperoxidase (MPO) activity, tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and KC ELISA.

RESULTS

CPT-11 caused significant diarrhea, histopathological alterations (inflammatory cell infiltration, loss of crypt architecture and villus shortening) and increased intestinal tissue MPO activity, TNF-alpha, IL-1beta and KC level and TNF-alpha immuno-staining. PTX inhibited delayed diarrhea of mice submitted to intestinal mucositis and reduced histopathological damage, intestinal MPO activity, tissue level of TNF-alpha, IL-1beta and KC and TNF-alpha immuno-staining. TLD significantly reduced the lesions induced by CPT-11 in intestinal mucosa, decreased MPO activity, TNF-alpha tissue level and TNF-alpha immuno-staining, but did not reduce the severity of diarrhea.

CONCLUSION

These results suggest an important role of TNF-alpha, IL-1beta and KC in the pathogenesis of intestinal mucositis induced by CPT-11.

Different susceptibilities of spontaneous rhythmicity and myogenic contractility to intestinal muscularis inflammation in the hapten-induced colitis

We examined the time-dependent changes in the immunoreactivity of the smooth muscle region and the accompanying motility disorder in a hapten-induced rat model of colitis. Histological analysis and myeloperoxidase (MPO) activity indicated that inflammatory cells infiltrated into the muscle layer at 2 days after 2,4,6-trinitrobenzenesulphonic acid (TNBS) treatment. The infiltrated immune cells then gradually decreased in number, but were still present at 14 days. The expression of proinflammatory cytokine mRNAs (TNF-alpha, IL-1beta and IL-6) and proteins in the muscle layer was increased at 2 days, then began to decrease, returning to control levels at 14 days. The frequency of spontaneous rhythmicity was suppressed at 2 and 7 days, and returned to control levels at 14 days. Consistent with these observations, the immunoreactivity of the interstitial cells of Cajal network was disrupted at 2 and 7 days, which then gradually reformed at 14 days. On the other hand, the myogenic contractions induced by high K(+) and carbachol were decreased at 2 days, and were still inhibited at 14 days. These results suggest that spontaneous rhythmicity dysfunction may improve more rapidly than myogenic contractility dysfunction in a hapten-induced rat model of colitis.

Interleukin-11 reduces renal injury and glomerular NF-kappa B activity in murine experimental glomerulonephritis

BACKGROUND/AIMS

There is now considerable evidence implicating T cells and macrophages in glomerular injury in crescentic glomerulonephritis. Recently, it has been shown that interleukin-11 (IL-11) has an immune modulatory function through its effect on both macrophages and T cells. We, therefore, examined the therapeutic effect of IL-11 in a murine model of experimental glomerulonephritis.

METHOD

Accelerated nephrotoxic nephritis was induced in C57BL/6 mice. IL-11 at a dose of 0.5 mg/kg/day (n = 10) in vehicle was given daily subcutaneously from the day of sensitization until day 14 after initiation of glomerulonephritis. Control mice (n = 10) received injection of vehicle alone with the same schedule.

RESULTS

IL-11 treatment markedly decreased albuminuria (6.2 +/- 1.9 vs. 18.2 +/- 4.5 mg/day, p < 0.05), the number of glomerular macrophages (1.1 +/- 0.2 vs. 1.7 +/- 0.3 cells/glomerular cross-section, p < 0.05) and glomerular fibrin deposition (fibrin score 0.9 +/- 0.3 vs. 2 +/- 0.3, p < 0.05). There was no difference in the glomerular T cell numbers between the IL-11-treated and the vehicle group. Glomerular NF-kappaB activity was markedly suppressed by 75% in the treated group (p = 0.0015).

CONCLUSION

In this study, we provide the first in vivo evidence that IL-11 treatment decreases glomerular NF-kappaB activity and reduces renal injury in experimental glomerulonephritis.

Altered epithelial cell lineage allocation and global expansion of the crypt epithelial stem cell population are associated with ileitis in SAMP1/YitFc mice

Crohn's disease is characterized by cycles of mucosal injury and ulceration followed by epithelial regeneration and restoration of normal epithelial function. In this study, we examined whether ileitis in SAMP1/YitFc mice, a recombinant-inbred line that spontaneously develops ileitis resembling human Crohn's disease, was associated with alterations in normal patterns of epithelial differentiation or changes in epithelial regeneration after experimental injury. Increased numbers of Paneth, goblet, and intermediate cells were present focally in the ileum of SAMP1/YitFc mice by 4 weeks of age, before any histological evidence of acute or chronic inflammation. This increase in secretory cells became more pronounced at sites of ileitis with increasing age and inflammation. Additionally, there was mispositioning of Paneth and intermediate cells along the crypt-to-villus unit. A concomitant reduction in the number of absorptive enterocytes was observed. In contrast to the ileal-specific changes in lineage allocation, crypt stem cell numbers began to increase in both the ileum and proximal jejunum at the onset of inflammation in SAMP1/YitFc mice. These data suggest that the alterations in epithelial cell differentiation and increases in the size of the crypt stem cell population observed in SAMP1/YitFc mice are regulated by distinct mechanisms. We speculate that these epithelial alterations may play a role in the pathogenesis of ileitis in this murine model of Crohn's disease.

Amount, Type, and Timing of Recreational Physical Activity in Relation to Colon and Rectal Cancer in Older Adults: the Cancer Prevention Study II Nutrition Cohort

Physical activity has consistently been associated with lower risk of colon cancer, but information is limited on the amount, type, and timing of activities. The relationship between physical activity and rectal cancer is unclear. We examined characteristics of recreational physical activity in relation to colon and rectal cancer in the Cancer Prevention Study II Nutrition Cohort of 70,403 men and 80,771 women (median age, 63 years); 940 colon and 390 rectal cancers were identified from enrollment in 1992 to 1993 through August 1999. The multivariate-adjusted rate ratios (95% confidence intervals) associated with any recreational physical activity compared with none were 0.87 (0.71-1.06) for colon cancer and 0.70 (0.53-0.93) for rectal cancer. Colon cancer risk decreased significantly with increasing total hours (P for trend without reference group = 0.007) and metabolic equivalent hours (P for trend = 0.006) per week of activities. No clear decrease in rectal cancer risk was seen with increasing hours per week of physical activity. Rate ratios (95% confidence intervals) were 0.72 (0.52-0.98) for &lt;2 hours, 0.68 (0.47-0.97) for 2 to 3 hours, 0.59 (0.41-0.83) for 4 to 6 hours, and 0.83 (0.59-1.16) for ≥7 hours per week of physical activity compared with none. Past exercise, as reported in 1982, was not associated with risk of either colon or rectal cancer. We conclude that increasing amounts of time spent at recreational physical activity are associated with substantially lower risk of colon cancer and that recreational physical activity is associated with lower risk of rectal cancer in older men and women.

Interleukin-10 and the regulation of mitogen-activated protein kinases: are these signalling modules targets for the anti-inflammatory action of this cytokine?

The many specific, yet overlapping and redundant activities of individual cytokines have been the basis for current concepts of therapeutical intervention. Cytokines are powerful two-edged weapons that can trigger a cascade of reactions and may show activities that often go beyond the single highly specific property that it is hoped they possess. Nevertheless, it can be stated that our new, though burgeoning, understanding of the biological mechanisms governing cytokine actions is an important contribution to medical knowledge. The crucial role of the anti-inflammatory cytokine, interleukin (IL)-10, in regulating potential molecular pathway mediating injury and cell death has attracted paramount attention in recent years. In this respect, the mitogen-activated protein kinase (MAPK) components have emerged as potential signalling cascades that regulate a plethora of cell functions, including inflammation and cell death. The biochemistry and molecular biology of cytokine actions, particularly IL-10, explain some well known and sometimes also some of the more obscure clinical aspects of the evolution of diseases.

Oral mucositis: time for more studies

Oral Mucositis (OM) is a frequent cause of severe morbidity in patients receiving chemotherapy and/or radiotherapy. The pathophysiology of OM involves direct cytotoxic effects, local inflammatory responses, and alterations in oral microflora. There are currently no approved agents for the prevention or treatment of OM. In this review we briefly describe current knowledge of the pathophysiology, clinical presentation, and management of OM. We then discuss investigational agents being studied in OM with a particular focus on local antimicrobial agents, hemopoietic growth factors, and cytokines. Measures to reduce the incidence of OM and/or alleviate its clinical sequelae should be incorporated into all chemotherapy or radiotherapy studies.

Redox- and oxidant-mediated regulation of interleukin-10: an anti-inflammatory, antioxidant cytokine?

Reduction-oxidation (redox) state constitutes such a potential signaling mechanism for the regulation of an inflammatory signal associated with oxidative stress. Interleukin (IL)-10 has recently emerged as an anti-inflammatory cytokine with antioxidant properties. Interestingly, redox- and oxidant-mediated pathways positively and/or negatively regulate the expression, distribution, and functional properties of IL-10, thus, allowing the evolution of what is known as an anti-inflammatory redox-oxidant revolving axis. This axis is directly involved in regulating phosphorylation mechanisms, which eventually control gene expression and the biosynthesis of oxidative stress-related cofactors, such as reactive species and inflammatory cytokines. The association between IL-10, an anti-inflammatory antioxidant, with redox- and oxidant-related pathways governing the regulation of inflammatory and closely dependent processes is thereafter discussed.

Mucosal tissue injury in cancer therapy. More than muscositis and mouthwash

PURPOSE

The purpose of this article is as follows: 1) to describe the characteristics and scope of mucosal tissue injury associated with cancer treatment; 2) to discuss recent advances in related basic and clinical science; and 3) to articulate research needs and opportunities to be addressed through collaborative interdisciplinary research.

OVERVIEW

Mucosal tissue injury is both a direct and indirect consequence of cancer therapy, with manifestations that include damage and a number of other potentially serious sequelae. Current research in mucosal tissue injury is focused on the biology, immunology, and genetics of mucosal injury; clinical problems; assessment and management; and processes and outcomes of care.

CLINICAL IMPLICATIONS

Results from these various areas of research enhance the understanding of the mechanisms of mucosal tissue injury, provide direction for the development of policy and for clinical practice, and help to define research needs and opportunities. Future research on the complex process of mucosal tissue injury will be interdisciplinary and will cross the boundaries among basic, translational, and clinical science.